Question: $ (0.02\% \div -3\%) \div 3\% $
Explanation: Convert each percentage into a decimal dividing by $100$ $ (0.000243 \div -0.03) \div 0.03 $ $ = 0.000243 \div (-0.03 \times 0.03)$ $ = 0.000243 \div -0.0009$ ${0}$ ${0}$ ${0}$ ${0}$ ${9}$ ${2}$ ${4}$ ${3}$ $\text{Shift the decimal 4 to the right.}$ ${2}$ $\text{How many times does }9\text{ go into }{2}\text{?}$ ${0}$ ${0}$ ${2}$ $-\vphantom{0}$ ${2}\div9={0}\text{ or }9\times{0} = {0}$ ${4}$ $\text{How many times does }9\text{ go into }{24}\text{?}$ ${2}$ ${1}$ ${8}$ ${6}$ $-\vphantom{0}$ ${24}\div9={2}\text{ or }9\times{2} = {18}$ ${3}$ $\text{How many times does }9\text{ go into }{63}\text{?}$ ${7}$ ${6}$ ${3}$ ${0}$ $-\vphantom{0}$ ${63}\div9={7}\text{ or }9\times{7} = {63}$ A positive number divided by a negative number is a negative number. $0.000243 \div -0.0009 = -0.27$ Convert the decimal into a percentage by multiplying by $100$. $-0.27 = -27\%$